workflows/ci.yml fix push branch regex

[scpeters]

🦟 Bug fix

Fixes triggering of GitHub workflows on branches with double-digit major version.

Summary

Ubuntu workflows for branches with a double digit major version number haven't been running for a while (6 months since the last sdf14 build). I believe this is due to the regex pattern used to match our release branches.

The current pattern matches the following:
"sdf", "sdf0", "sdf1", ..., "sdf8", "sdf9"
of which "sdf" is incorrect, and only "sdf9"
is currently supported. This updates the pattern
to match single digits "sdf1" - "sdf9" and double
digits "sdf10" to "sdf99".

I don't think we can test this without merging it?

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[scpeters]

the Noble workflow failure is due to gazebo-tooling/action-gz-ci#76